Blood analyser with out-of-focus image plane analysis and related methods

Abstract

A blood analyser and related methods, in particular a method of analysing a blood sample is disclosed. The blood analyser comprises a memory, an interface, and one or more processors. The blood analyser is configured to obtain image data of a prepared blood sample; select a first image associated with a first image plane of the prepared blood sample from the image data; characterize the first image, wherein the characterization of the first image comprises to determine a first set of cell regions belonging to the first image plane; select a first distal image associated with a first distal image plane on a distal side of the first image plane, and determine a first distal set of distal cell regions associated with the first set of cell regions; and determine a first cell parameter for each cell region of the first set of cell regions based on the first distal set of distal cell regions.

The invention claimed is: 
     
         1 . A blood analyser, the blood analyser comprising a memory, an interface, and one or more processors, the blood analyser being configured to:
 obtain image data of a prepared blood sample, the image data comprising data of a stack of images where each image of the stack of images is associated with an image plane, wherein each image plane is associated with a different height along a z-axis of the prepared blood sample;   select a first image associated with a first image plane of the prepared blood sample from the image data;   characterize the first image, wherein the characterization of the first image comprises determining a first set of cell regions belonging to the first image plane, wherein a cell region of the first set of cell regions is associated with a group of pixels in the first image representing one or more cells, a part of a cell, parts of cells, or an optical phenomena relating to one or more cells;   select a first distal image associated with a first distal image plane on a distal side of the first image plane, and   determine a first distal set of distal cell regions associated with the first set of cell regions, wherein a cell region of the first distal set of cell regions is associated with a group of pixels in the first distal image representing one or more cells, a part of a cell, parts of cells, or an optical phenomena relating to one or more cells, wherein the determination of the first distal set of distal cell regions comprises determining that the first set of cell regions do not belong to the first distal image plane; and   determine a first cell parameter for each cell region of the first set of cell regions based on the first distal set of distal cell regions.   
     
     
         2 . The blood analyser according to  claim 1 , wherein the blood analyser is configured to select a primary intermediate distal image associated with a primary intermediate distal image plane on a distal side of the first image plane, and to determine a primary intermediate distal set of distal cell regions associated with the first set of cell regions, and wherein the first cell parameter for each cell region of the first set of cell regions is based on the primary intermediate distal set of distal cell regions. 
     
     
         3 . The blood analyser according to  claim 2 , wherein the selecting a first distal image is based on the primary intermediate distal set of distal cell regions. 
     
     
         4 . The blood analyser according to  claim 1 , wherein the blood analyser is configured to select, from the image data, a first proximal image associated with a first proximal image plane on a proximal side of the first image plane; and to determine a first proximal set of proximal cell regions associated with the first set of cell regions; and wherein the determination of the first cell parameter is based on the first proximal set of proximal cell regions. 
     
     
         5 . The blood analyser according to  claim 4 , wherein the determination of the first cell parameter comprises determining a first proximal cell parameter for each proximal cell region of the first proximal set of cell regions and wherein the first cell parameter is based on the first proximal cell parameter for the associated proximal cell regions of the first proximal image plane. 
     
     
         6 . The blood analyser according to  claim 5 , wherein the first distal cell parameter and/or the first proximal cell parameter comprises one or more of a colour/contrast parameter, a geometry parameter, a morphology parameter, and a cell classification/type parameter. 
     
     
         7 . The blood analyser according to  claim 4 , wherein a first distal distance between the first image plane and the first distal image plane, and a first proximal distance between the first image plane and the first proximal image plane are in the range from 2.5 μm to 75 μm. 
     
     
         8 . The blood analyser according to  claim 4 , wherein the first proximal image plane is associated with a first proximal height in the prepared blood sample, the first proximal height being different from the first height. 
     
     
         9 . The blood analyser according to  claim 4 , wherein the determination of the first proximal set of proximal cell regions comprises determining that the first set of cell regions do not belong to the first proximal image plane. 
     
     
         10 . The blood analyser according to  claim 1 , wherein the blood analyser comprises a classification circuitry configured to operate according to a classification model, and wherein the determination of the first cell parameter comprises classifying each distal cell region of the first distal set of distal cell regions. 
     
     
         11 . The blood analyser according to  claim 1 , wherein the determination of the first cell parameter comprises determining a first distal cell parameter for each distal cell region of the first distal set of distal cell regions and wherein the first cell parameter is based on the first distal cell parameter for the associated distal cell regions of the first distal image plane. 
     
     
         12 . The blood analyser according to  claim 1 , wherein the blood analyser is further configured to determine a first blood parameter of the prepared blood sample based on the first cell parameters. 
     
     
         13 . The blood analyser according to  claim 1 , wherein the first image plane is associated with a first height in the prepared blood sample. 
     
     
         14 . The blood analyser according to  claim 1 , wherein the first distal image plane is associated with a first distal height in the prepared blood sample, the first distal height being different from the first height. 
     
     
         15 . A computer program product comprising a non-transitory computer readable medium, having thereon a computer program comprising program instructions, the computer program being loadable into a data processing unit and configured to cause execution of the operations according to  claim 1  when the computer program is run by the data processing unit. 
     
     
         16 . A method of analysing a prepared blood sample, the method comprising:
 obtaining image data of the prepared blood sample, the image data comprising data of a stack of images where each image of the stack of images is associated with an image plane, wherein each image plane is associated with a different height along a z-axis of the prepared blood sample;   selecting a first image associated with a first image plane of the prepared blood sample from the image data;   characterizing the first image, wherein the chacterizing the first image comprises determining a first set of cell regions belonging to the first image plane, wherein a cell region of the first set of cell regions comprises a group of pixels in the first image representing one or more cells, a part of a cell, parts of cells, or an optical phenomena relating to one or more cells;   selecting a first distal image associated with a first distal image plane on a distal side of the first image plane, and determining a first distal set of distal cell regions associated with the first set of cell regions, wherein a cell region of the first distal set of cell regions comprises a group of pixels in the first distal image representing one or more cells, a part of a cell, parts of cells, or an optical phenomena relating to one or more cells, wherein the determination of the first distal set of distal cell regions comprises determining that the first set of cell regions do not belong to the first distal image plane; and   determining a first cell parameter for each cell region of the first set of cell regions based on the first distal set of distal cell regions.